Mission Mistletoe
by shyesplease
Summary: Simultaneously, Casey's eyes and mouth popped open comically. "Is-Isn't there some type of r-rule or stipulation that says you can't kiss the same person in the same night or something!" she frantically stuttered. One-Shot. Dasey.


**A/N:** HAPPY HOLIDAYS EVERYONE! I'm very well aware that it is after Christmas, but this idea popped up between a friend and I recently, so I didn't have the time to post it before Christmas like I really wanted. I hope you guys still like it and enjoy! I hope you all have had a pleasant holiday season and Happy New Year! :)

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><p>"I can't believe my mother had the audacity to wait so last-minute to not only decorate, but to tell me that she invited a bunch of people over here for a Christmas party. Tomorrow!" Casey exclaimed as she pushed and pulled through a mountain of boxes to get to the Christmas decorations.<p>

Derek leaned back against one of the basement's cinderblock walls, watching her navigate through the cardboard jungle of junk both of their families had stored. "Not to mention that Vicky is coming," he helpfully added with a smirk.

Derek thought he heard his stepsister growl, but it was hard to be sure with so many walls of boxes between them. "Thanks for that lovely reminder," he heard her mutter, to which he chuckled to.

"Would you be useful for once in your life and help me?" she hollered, her voice faintly strained. "I think I finally found the decorations."

He kicked off the wall, but didn't move any further to aid her. "Help? I'm sorry, but I don't think I know the meaning of that word."

"You don't know the meanings to a lot a words, I know," she snapped dryly. "I'll get you a dictionary for Christmas. Right now, though, I need you to get over here and take some boxes!"

A loud thud and the sound of glass shattering then echoed off the walls. Derek quickly ran to where he thought he heard the noise, hoping Casey hadn't klutzilla-ed too bad to warrant a hospital visit.

When he arrived to the spot, Casey was standing stock still in fright. He let out a relieved sigh upon seeing her unscratched, despite being surrounded by some broken ornaments.

"Jeez, Case. I know you're not happy about the party, but no need to sabotage it."

Her eyes snapped up to his with a fierce fire burning behind her eyes. "Der-ek! This is all your fault! Look what you made me do?!" she shrieked, gesturing to the mess around her.

"My fault?" Derek repeated unbelievably. "It's not my fault _you_ couldn't wait 2 seconds for me to get here!"

"Just,_ here_," she said, shoving a box roughly into his chest. "Take this to the living room," she instructed, already turning away from him to go through other boxes.

Derek made a face at her, before peering into the box she gave him. He could see some garland, fake poinsettias, a couple things of mistletoe…

Smirking, Derek took out a sprig. "Case, are you really so desperate for an excuse to kiss me that you'd hang up some mistletoe?"

She threw a wreath at his head.

…

The party was in full swing. Christmas music was blasting while relatives from both sides of the family were conversing and laughing. They had a better turn out tonight than the one for the McDonald-Venturi wedding.

Somehow, despite their lack of time, they were able to get a tree and get most of the decorating done. Apparently being the parents of only a few months old baby caused a few memory lapses.

Glancing around the room, Derek watched his Dad and Nora walk around, making small talk with their various guests. Edwin, Lizzie, and Marti were playing a game with some of his uncle's younger kids. Robby, his new baby brother, was being coddled by some old looking lady that he had to assume was on Casey's side of the family since he didn't recognize her.

Sweeping his eyes across the room again, he frowned when he didn't see Casey anywhere. But just as he had that thought, he saw a ponytailed-head bob across the opening of the kitchen doors. _What was she doing?_

He left the food table and walked to the kitchen, squeezing through the two doors. There she was taking out a batch of brownies from the pan, humming along to the Christmas song that was playing in the next room.

"Hiding from all the crazy relatives?" he asked, walking further into the kitchen.

She jumped in surprise, having not heard him enter. She then laughed, shaking her head. "Just trying to finish the baking. With hounds like you Venturis, there can never be enough."

"Very true," he admitted with an easy smile. He saddled up next to her at the counter to steal one of the brownies. "Mmmm," he moaned as its chocolatey goodness erupted his taste-buds. Casey snickered over his behavior, and Derek smirked as best as could between his chews.

"So, are you ever going to grace your presence, McDonald?" Derek asked after he swallowed down his treat, nodding to the party.

"Yes," she answered, placing the last pieces of the brownies onto a plate. "I've got a batch of cookies in the oven that are almost done and then that's it." Derek nodded and stole another brownie.

She blew out a breath, sighing. She leaned her hip against the counter and watched him amusingly as he chewed. He raised an eyebrow at her. "What?"

Her eyes immediately dropped to the floor. "Nothing, um, how is everything out there though? I haven't heard any screams or broken dishware, so I guess well?"

"Yeah, it seems like everyone is having a ball. My Aunt Madge and your grandmother are strangely hitting it off too," he responded with a quirk to his lips. "Though every relative I talk to has to ask me the same damn questions," he droned, rolling his eyes. "Maybe I should make an F.A.Q. and print it to a shirt or something."

"Maybe that's what I can get you for Christmas," Casey thought aloud, grinning wickedly at him.

"But I thought I was getting a dictionary, Case!" Derek said back with an embellished frown. He took a step closer to her and put his hand to his heart, as if it was paining him. "I was _really_ looking forward to that."

"Oh, I'm sure you were," she drawled, patting him on the shoulder as if to comfort him.

Casey instantly fell into a fit of giggles. Derek laughed too, breaking his charade. It was then that he noticed something above his head. Derek leaned back to get a better look and his eyes immediately widened.

After a lapse of silence, he heard Casey take a quick intake of breath. The action was what finally tore Derek's gaze from the mistletoe to his stepsister, who had a look of shear panic embedded on her face that he could only guess was mirrored on his own.

"Uh…we – I mean," he started stupidly, wildly gesturing to the plant above their heads.

"Well, we…could…" Casey said, blushing profoundly at her admission.

"_Really?_" he squeaked. He cleared his throat. "I mean, it's – it's not a…big deal…"

"Right," she let out breathlessly. "Just a…friendly, familial kiss…for a tradition!"

"Exactly," he agreed, trying to swallow down his fear.

"So I guess we -" she began, stepping closer.

"Yeah…" he breathed out, hesitantly reaching out to her, but quickly withdrew when his hands wouldn't stop shaking.

Their eyes watched each other cautiously as the distance between them got smaller and smaller, only closing when their noses bumped. Their lips found each other in an innocent peck, only brushing against each other enough for Derek to think he could taste small remnants of brownie batter.

He'd like to say that the song that was playing when they kissed was something corny as hell, like "All I Want For Christmas Is You," but as they slowly pulled away, Derek could clearly hear "Grandma Got Ran Over By A Reindeer." But he could oddly relate to it, having felt like he just got nailed and trampled by eight reindeer himself, especially when her eyes slowly opened and locked right on his.

"Not a big deal," he rasped out. His eyes quickly flickered down to her lips.

"Right," she let out, her brows furrowing, "I -" A ding from the oven rang, indicating her cookies were done baking. "I – I should get the cookies, and you should get back to the party."

…

Like she promised, Casey joined the party after she took out the last batch of cookies. However, she was also keeping herself at about a 5 meter radius away from him at all times. Derek sighed.

He always kinda had a thing for Casey, though for a while it was purely attraction. So, naturally he had always thought about what it would be like to kiss Casey, erm, amongst other stuff too. But Derek never thought he'd ever get to actually outlive one of his fantasies, regardless how PG it ended up being.

And now that he found out that the experience lived beyond expectations, he wanted more. He just didn't know how to go about that, especially when it looked like she was currently avoiding him.

"Hey there, cuz," Vicky greeted cheekily as she came up next to him at the food table.

"Hey, Vicky. Long time, no see," he said. "Not that I'm complaining," he added with a charming smirk.

Vicky forced a laugh. "Oh, Derek! You were always so _so_ funny. Been defending Casey's honor anytime recently?"

Derek's eyes thinned, but he kept his grin intact. "Luckily there hasn't been any cheating boyfriends or backstabbing cousins at Queens. So, no."

Vicky crossed her arms and looked around the party area just as he was. "Look, I know what I did was fucked up. I had a few drinks and the residual jealousy I had for Casey came rushing forward…"

Derek hiked up an eyebrow. "I'm not asking for a heart to heart here."

Casey's cousin rolled her eyes. "Listen, Fonzie, I just wanted to let you know that if you are going to make a move on Casey, make it already! You guys are slower than watching grass grow!"

"And just why would I make a move on Casey?" he asked, trying to keep his voice even.

The girl snorted. "You've only been looking at her all night. Plus," she said, an evil glint to her eyes. "I saw your little smooch in the kitchen earlier."

Derek visibly paled. "That – That was because the mistletoe, you know. Tradition!"

"Stop kidding yourself," she said. "Even during my mother's wedding fiasco, I knew you had a hard-on for her."

Derek scrunched his eyebrows downwards and frowned. "What do you get out of this, Vicky?"

She shrugged. "It sure as hell would make things more interesting around here…"

Derek looked over at Casey, who was chatting pleasantly with his Aunt Jolene. Her eyes then flickered over to him, making his heart bungee jump. However, her eyes immediately traveled to the brunette next to him and she scowled before turning away.

"So, what do you think I should do?" he asked, wringing his hands around his neck nervously.

Vicky turned to him with a coy grin.

…

He couldn't believe that he was taking Vicky's advice of all people, but he realized that he really needed to tell Casey how he felt already. There had been plenty of times over the years when he could've told her, but he always chickened out. Even now as he was hanging up a mistletoe over the back door, he had the strongest urge to completely forget this whole thing and tell Vicky to shove it.

The plan was for Vicky to lure Casey to the spot where Derek hung the mistletoe so that he could kiss her again in hopes that she would be Casey and want to talk about it. Because the thought of just coming out of the blue and confessing his…_feelings_ was making his stomach churn in waves of tsunami proportions. Plus, he couldn't just kiss her out nowhere like they were in some old romance film. What if she slapped him and refused to talk? So, he needed an excuse of sorts, hence the mistletoe.

Having securely placed the mistletoe, Derek sat down on the wooden bench that they had on the porch, waiting for Vicky to execute her portion of the plan. His legs were jittering up and down in nervous anticipation, but the motion was welcomed since it was also helping him keep warm out in the frigid winter weather.

A minute later, he heard two voices drawing nearer. His heart jumpstarted and began beating erratically. Despite the cold, his palms felt like they were starting to get clammy.

"Come on, Casey, I want to show you how pretty the snow looks out here," Derek could hear a slightly muffled Vicky say behind the door.

A pair of boots could be heard clacking against the laundry room's tile. "Why can't we just look out the kitchen window?" Casey reasonably asked.

"Where would the fun be in that?" Vicky answered, and Derek knew she was probably grinning mischievously.

The door handle turned and the two girls stepped outside.

"Derek?" Casey said straightaway with an upturned eyebrow, confused by his presence.

Being distracted as Casey was, Vicky used this moment to run back inside, slamming the door behind her.

Casey instantly whirled herself around at the noise. She rushed to the door, trying to turn it, but alas, it wouldn't open. "Vicky!" she hollered, banging against the door. His stepsister's shoulders slumped. "She locked the door," she stated miserably.

"What?!" he exclaimed, trying to sound astounded, when in all actuality this was part of the plan. He strode over to the door next to Casey, seemingly making an attempt to open the door himself.

Casey sighed. "I guess we'll have to walk around to the front. No one is going to hear us back here with the music." She turned to do just that, but Derek reached out to grab her upper arm.

"Hey, look," he said, pointing up to the mistletoe with a satisfied smirk. This plan couldn't have gone any smoother.

Simultaneously, Casey's eyes and mouth popped open comically. "Is-Isn't there some type of r-rule or stipulation that says you can't kiss the same person in the same night or something?!" she frantically stuttered.

Chuckling, Derek shook his head. "No, I don't think so."

"Fine, just – just get it over with," she muttered, closing her eyes tightly.

Although his hands were shaking like last time, he still used them to cup her face – at least now he could blame the cold if she asked about them trembling. He pulled her face forward as he dipped his head down until their lips collided halfway. But this kiss was not a mere peck like before. It was still closed-mouthed, but Derek lingered, holding on until Casey stepped away a few seconds later.

"Um," Casey let out timidly, tucking a loose strand of her hair behind her ear. "I guess we better go."

"Wait!" Derek said, holding up an arm to prevent her from leaving. "That's it? That's all? You're not going to say anything about this?"

"What do you want me to say, Derek?" she implored, tilting her head to the side as she regarded him strangely, looking up into his eyes puzzlingly. "I'm not one of your bimbos who's going to rave over you."

Derek's expression turned hard. "I'm not asking you to rave over _anything_! I just thought you'd want to talk about this since we've kissed twice in two hours!"

"Well, I don't," she seethed resolutely.

"Great," he angrily snarled.

Small puffs of their breath were intermingling in the cold air as they both glared severely at the other. Although rather infuriated with her, Derek wanted nothing more than to kiss her now, again. Seeing her just as pissed and full of fierily passion was only heightening the desire.

Casey abruptly broke their stare and strode away without another word or glance. Derek watched after her until she rounded the house and then he plopped himself back on the bench in defeat.

A soft click sounded and the back door soon opened to reveal Vicky. "So what's next, Romeo?"

…

"Your _big_ plan is to hang up _another_ mistletoe?" Vicky dryly asked as she watched him fasten another one of the little plants above the bathroom door. "Didn't you strike out doing that, like, 30 minutes ago?"

Derek rolled his eyes with a grunt. "Will you stop badgering me and keep an eye out like I asked you to?"

"I'm just saying," she said defensively, sticking her tongue out at him. Nevertheless, Vicky did turn back around to keep her eye on the hall, making sure no one was on their way. "But wouldn't it be easier to just tell her?"

He was already feeling nauseous at the mere suggestion of it. He swallowed down the feeling. "No, no it wouldn't be easier."

"So, do you need me to lure her to the spot again?" she asked over her shoulder.

Finished, Derek jumped off the stool he was using and replaced it back into the bathroom. "No, you're not needed at all after this," he said. "I'm just going to wait until she comes out of the bathroom. She'll have to eventually."

"She might not come up for another couple hours to use the bathroom!" Vicky pointed out, looking at him incredulously.

"Then, I'll have to wait," he countered with a simple shrug.

Vicky opened her mouth to say something, but quickly froze. She then looked up at him. "Someone's coming!" she whispered frantically before sprinting to Lizzie's room to hide.

Derek followed suit, but ran to his own room. He shut the door, but kept it open a sliver so he could look out into the hallway. Sure enough, it was Casey who had come up. She bristled by his room and entered the bathroom.

Taking a deep breath, Derek opened his door and walked out, his eyes flittering towards the staircase to make sure no one else was on their way up. Not hearing anyone else, he waited impatiently in the middle of the hall. He didn't want to get too close to the bathroom just yet. He wanted his run-in to appear as accidental as possible.

Hearing the handle jiggle, Derek took the steps over to the bathroom. He timed it just perfectly so that when Casey opened the door and stepped over the threshold, he bumped right into her. He even had to reach out and catch her or else she would have fallen on her ass. He stifled a laugh as he helped steady her balance. "You okay?" he asked with an upturned grin.

She averted his eyes by trying to smooth down the wrinkles in her clothes. "Do you ever watch where you are going?" she barked.

"Wow, Case. We really need to stop meeting like this," he instead said.

Casey scrunched her face inwards, twisting her lips. She followed the direction his eyes followed and quietly mutter, "Oh, god."

"Looks like we're going to have to kiss again," Derek commented, trying to seem uninterested.

Casey eyed him suspiciously. "Derek, we've kissed twice today. Twice! I think that's enough for a lifetime. Can we just pretend we didn't see it and go our separate ways?"

"It's tradition!" Derek proclaimed, "Plus, isn't that bad luck? It seems like it would be bad luck."

"That's a chance I'm willing to take," she grumbled, ready to move past him.

Derek grabbed her by the waist, pulling her close to him. "I'm not. I'm very superstitious," he said softly, his words ghosting over her lips because of their close proximity.

He watched her eyes glance down at his lips. He thought that was a victory in itself, but it was nothing compared to when she suddenly leaned forward and kissed him on her own accord. The action was surreal. Derek was stunned still at first, but quickly he gripped her hips and kissed her back with as much feeling as he could convey. But strangely enough, the emotion emitting off of Casey felt very sorrowful.

Having sensed such a polar feeling than his own, Derek was the one to step back from the kiss. He watched Casey's eyes open back up slowly, her eyes resembling that of a cloudy day than a clear sky. "Case," he whispered worriedly, "are you okay?"

"I need to get back to the party," she recited back to him, before scurrying away and down the stairs.

Derek stood frozen in the doorway, unsure of what happened and what to do next. Was kissing him that depressing or was it something else plaguing her mind?

"Hey, Johnny Bravo," Vicky's voice rang through the empty hallway. "Go after her."

…

He quickly ran down the hallway and scrambled down the steps. He instantly saw Casey making her way towards the front door, so Derek weeded his way through their relatives exactly when Casey opened the entrance to leave.

"Hey," he said softly, grabbing her elbow to pull her back into the house's warmness. "Where are you going? What's wrong?"

She sniffled and Derek's body promptly went rigid at the sound.

"I just need to get out of here," Casey confessed.

Derek nodded to her. "Do you need me to take you somewhere?" he kindly offered.

She stared up at him, eyes wet and piercing. "Oh," he let out, dejected. An epiphany hit him. "You need to get away from me."

He looked down at the hardwood floors and shuffled his feet. So the one thing he feared these past couple years actually happened; Casey was rejecting him.

Derek blew out a breath. "Am I that bad of a kisser?" he tried to joke, but it made him feel pathetic.

Casey chortled over a sob. She opened her mouth to say something, but she was cut off by Marti hollering, "OOH, CASEY AND DEREK ARE UNDER THE MISTLETOE!"

Derek and Casey's heads both snapped up above them and there indeed was a mistletoe there.

"You gotta be freakin' kiddin' me," Casey mumbled, a few more tears escaping out of frustration.

Ignoring the ever-growing pairs of eyes on them, Derek looked over at Casey. "We don't have to kiss, Case," he told her seriously and intensely. "I can tell that you hate it and I'm sorry for setting up those mistletoes. I'm an idiot, I know. I'm sorry."

"You – You set up all the mistletoes?" she asked dazedly, as if the concept was hard to grasp.

Their gawkers were silent, not even whispering. Someone even shut off the music so everyone could hear their conversation better – nosey bastards.

"Well, not the first time, or this one," he admitted, looking up at the sprig, "but I set up the ones at the back door and upstairs."

Her eyebrows deepened and her lip snarled. "Why the hell would you do that?" she hollered. "Did you finally find my diary and decide to stoop this low to prank me?!" More angry tears fell down her face.

Derek took a hesitant step back, slightly petrified of his stepsister's sudden wrath. "Diary? What the hell does your diary have to do with anything?" he questioned. "I set up the mistletoes because it was an excuse to kiss you and a half-assed way to tell you how I feel."

He heard a few gasps slip out of some people's mouths behind him. He thought he even heard Felicia let out a small "Oh!"

Casey faced softened reasonably at his confession. "What?" she breathily asked.

Derek steeled himself, trying to conjure enough courage to declare his…_feelings_ for her, while also trying to keep his stomach at bay. He could feel himself turning green and this was far from how he ever pictured this happening, but it needed to be done.

"I like you, Case," he said, looking into her eyes imploringly. "Really, really like you. Enough to concoct foolish, rash plans to get you to kiss me in hopes that you'd say something first…" he trailed off and looked at her watery eyes. It pained him to see her in that state. "But you didn't, and that's okay, really. I get it. You don't like-"

He was cut off by her lips pressing urgently against his and her hands holding on to his biceps in a firm clasp. His mind went blank, but he let himself just feel the moment before it passed. Even if this was some evil scheme of revenge on Casey's part, he wanted to milk it for all it was worth.

Casey all too soon pulled away, but she rested her forehead against his affectionately. Derek almost whined because she shouldn't be allowed to do these type of things when she was just going to kick him in the balls, metaphorically of course – or literally, if she was really that mad at him.

"I like you too," she whispered.

Derek jerked backwards in surprised and took her face in. He eyed her doubtfully. "Since when?!" he couldn't help but ask.

Casey looked at the crowd still watching them. "Do you people have nothing else to do with your lives?" she asked, pushing Derek outside with her and shutting the door to give them a little more privacy.

She walked silently to the porch steps and sat down, sighing. Derek followed her lead and sat down next to her. They didn't speak at first. Behind him, Derek could hear the music turn back on, but he could see some people peeking their heads out the window, still curious.

He cleared his throat. "Since when have you liked me?" he asked again, prompting her to speak.

"Senior year," she answered, dipping her head down shyly.

Derek eyebrow rose. "Really?" he wondered aloud. "Well, I had you beat," he said, bumping into her shoulder playfully. He could see her lips curve into a nervous smile. "Sophomore year."

"What?!" she exclaimed, turning to look at him. "No, you didn't! You're just saying that so it'll look like you liked me longer."

Derek laughed loudly at that, because as ass-backwards as that sounded, he could see them actually doing that just to feel like they one upped the other. "Whether you believe me or not, it's true," he told her, bravely reaching out to intertwine their hands.

Casey squeezed his hand. "You never seemed to like me like that…"

"Well, you never did either," he pointed out, smirking.

"You like me," she said in a daze, her eyes shining.

Derek rolled his eyes, but he was sporting a dopey smile. "Yes, Casey. I like you. You like me. Can I finally kiss you without a mistletoe now?" he said, leaning closer to her with every word.

She wrapped her arms loosely around his neck. "I think I would be okay with that arrangement," she said, flashing him a smirk that highly resembled his own.

"Good," he stated, and then pulled her to him so that she was now in his lap. "Now help warm me up because I'm freezing my ass off!"

"Der-ek!" she hollered while laughing, but it was soon silenced by Derek kissing her soundly.


End file.
